1578 



ROTHROCKIA 



5-parted; stigma abruptly produced from * 

 column having a 3-crested apex. feyn. Flora N. 

 vol. 2, part 1, p. 403. 



near the borders of Arizona f ' 



EOUGE PLANT, .Rimta humilis. 



(probably a native name in Guiana), Also 

 Proteace* 



s opa,,. 

 about 40 species of the tropical regions of b. 

 Thev are mostly woody plants, with handsome ever- 

 green Ivs. either simple or pinnate: fls. usually mcon- 

 Dicuous in axillary or lateral racemes, pedicelled in 

 S hermaphrodite, regular ; perianth cylindrical 

 rather SSSSt, but little dilated at the base; the limb 

 somewhat globular: ovary sessile; ovules 2, pendulous, 

 orthotropous. 



A. Hairs rust-colored. 



Pdhlii, Meisn. (R. Corcovadensis, Hort.). A tree 

 with branches clothed with rusty colored woolly 

 tomentum: Ivs. 1 ft. or more long, pinnate, with 

 5-8 pairs of Ifts. which are 3-5 in. long, on 

 stout petiolules 1 in. or less long, ovate or ob- 

 liquely ovate, acuminate, acutely serrate : ns. 

 % 1 in. long, white or yellowish, in nearly ses- 

 sile axillary racemes 3-5 in. long. B.M. 00!)o. 



AA. Hairs golden. 



aurea, Linden. According to Belg. 

 Hort. 1866:202, this species was named 

 for the golden hairs covering the 

 upper parts of the stem and pet- 

 ioles. Brazil. -Rare and imper- 

 fectly known, but still offered in 

 America. 



R. Jdnghei, Hort., is a plant offered 

 by Siebreeht which does not appear 

 in botanical works. 



F. W. BARCLAY. 



ROWAN. Sorbus Aucuparia. 

 ROYAL CROWN. JSucomis. 



ROYAL FERN. Osmunda re- 

 galis. 



ROYAL PALM. 



regia. 



Oreodoxa 



RUBUS 



EUBBER PLANTS. Various plants furnish Rubber, 

 The best gutta percha is said to be produced by Isonan- 

 dra Gutta (which see), a native of India. For the Rub- 

 ber Tree of South America, see Hevea Brasiliensis, p. 

 741. The Rubber Tree of tropical Africa is Landolphia 

 florida; see B.M. 6903. The Rubber Plant of horticul- 

 turists is Ficus elastica. 



RUBIA (Latin, red; referring to the color of the dye 

 extracted from the root). Rubidceie. It. tinctorum is 

 the dye-plant called Madder, the 

 long, fleshy roots of which are ground 

 to powder. According to Thorburn, 

 Madder furnishes a good green fod- 

 der if cut the second year when in 

 flower. The genus consists of about 

 30 species of scabrous, hispid or 

 prickly herbs widely scattered about 

 the world, mostly in the temperate 

 regions. Lvs. in whorls of 48 or 

 rarely opposite : Ivs. small to minute, 

 in axillary or terminal cymes, 5-mer- 

 ous ; involucre none ; calyx - limb- 

 wanting ; corolla rotate or rotate- 

 bell-shaped, 5-lobed: ovary 2-loculed 

 or abortively 1-celled. 



tinctdrum, Linn. (B. tinctdria, Salisb.). MADDER. 

 A scandeiit herbaceous perennial: Ivs. 2-4 in. long, 

 sessile or very short-petioled, mostly lanceolate, not 

 cordate, in whorls of 4-6: cymes terminal, panicled, 

 spreading, leafy. p. \\r. BARCLAY. 



2191 To ui us t ra te the 



ROYAL PEACOCK FLOWER. BLS 



Poinciana regia. 



If the mam cane or 



ROYENA (Adrian van Royen, ste >m on the left grew in 



professor of Botany in W of gUft^-g-gl 



Leyden; died 1(79). lJbenacea>. an d at the close of the 



Royena lucida is one of the old- season of 1900,the whole 



time Cape shrubs formerly cult, cane had died or be- 



under glass for ornament in Eng- come very weak. If the 



land and lately offered in S. Cali- cane had been examined 



fnrnin Tt hn small whif-p fl in the spring of 1900, the 

 torma. It has small wnite fls. bud would hftve been 



about Y* m. across, with 5 more seen (as above A) from 

 or less reflexed lobes. Royena which was to grow the 

 is a genus of about 13 species of fruit-bearing shoot. 

 evergreen shrubs or small trees, 



2 of which are native to tropical Africa and the rest to 

 the Cape. The genus is distinguished from the 4 or 5 

 other genera of the ebony family by the flowers being 

 hermaprodite instead of dioecious and the stamens in a 

 single series. Other generic characters (taken from the 

 Flora of Tropical Africa) : calyx often accrescent in 

 fruit; lobes 5, rarely 4; corolla bell- or urn-shaped, 

 5-cleft; lobes reflexed; stamens 10, inserted at the base 

 of the corolla - tube : ovary conical; styles or style- 

 branches 2-4: fr. globose to oblong, leathery, indehis- 

 cent. 



lucirta, Linn. Tender shrub: Ivs. ovate, the younger 

 ones silky: peduncles about a third as long as the Ivs.: 

 corolla bell-shaped. S.Africa. B.R. 32:40. 



RtTBUS (Latin name, ultimately connected with 

 ruber, red). Rosdcew. BRAMBLE. BLACKBERRIES and 

 RASPBERRIES. A most variable and puzzling genus, 

 containing perhaps 200 fairly well-marked species and 

 numberless intermediate forms. As many as 1,500 spe- 

 cies have been described. The genus is particularly 

 strong in Europe, where the greatest number of specific 

 names have been made (see Weihe & Nees, "Rubi 

 Germanici," 1822-7; Focke, "Synopsis Ruborum Germa- 

 nic," 1877; Babbington, "British Rubi," 1809; W. M. 

 Rogers, "Key to the British Rubi," Journ. Botany, 1892). 

 Focke describes 72 species inhabiting Germany. There 

 is also a large extension of the genus in the Himalayan 

 region, about 50 species being recognized (J. D. Hooker 

 admits 41 species in the "Flora of British India"). The 

 species extend eastward into China and Japan. Hemsley, 

 in his "Flora of China," admits 41 species. In Japan, 

 Franchet and Savatier admit 22 species. In North 

 America, about 40 species are now recognized, but they 

 have not been studied critically, and it is probable that 

 many more specific types will be recognized in the near 

 future. No end of "species could be made, but it is 

 doubtful whether a great multiplication of species- 

 names would contribute anything more than confusion 

 to the literature and knowledge of the genus. There is 

 no monograph of the American species. The species 

 that are valuable for their fruits are reviewed by Card in 

 "Bush-Fruits" and by the present writer in "Sketch of 

 the Evolution of our Native Fruits," 1898. Rubus is 

 widely distributed in the northern hemisphere, particu- 

 larly in temperate and warm-temperate parts. Some 

 of them are alpine and arctic. In tropical countries the 

 genus is relatively poorly represented. Oliver admits 

 only 4 in the "Flora of Tropical Africa." Only 2 species 

 are described in Grisebach's "Flora of the British West 

 Indies." Baker admits 3 species in the "Flora of Mau- 

 ritius and the Seychelles." Hillebrand describes 3 spe- 

 cies in "Flora of the Hawaiian Islands." The southern 

 hemisphere has few species. Bentham's "Flora Austra- 

 liensis" has but 5 species. Kirk's "Flora of New Zea- 

 land " mentions only 4 indigenous species. There are 

 also 5 species described in Harvey and Sender's work 

 ("Flora Capensis") on the flora of the Cape of Good 

 Hope region. 



Rubus is closely allied to Rosa, from which it differs 

 chiefly in the structure of the flower. In Rosa, the 

 torus is hollow (formerly said that the calyx is hollow 

 or urn-shaped) and contains the dry fruits or akenes. 

 In Rubus the torus is convex, conical or elongated, and 

 bears the mostly soft or pulpy fruits on its surface. 

 Rubi are chiefly shrubs with stems (canes) that die 



